Cradle assembly for stranding machine



Sept. 15, 1959 E. P. GIESEKE 2,903,842

CRADLE ASSEMBLY FOR STRANDING MACHINE Filed June 2, 1958 I 2 Sheets-Sheet 1 Ticrl.l. k

INVENTOR.

LCDWA PD P 5/555/(5 BY B B United States Patent CRADLE ASSEMBLY F OR STRANDING MACHINE Edward P. Gieseke, Lincroft, NJ., assignor to Syncro Machine Company, Perth Amboy, N.J., a corporation of New Jersey Application June 2, 1958, Serial No. 739,213

5 Claims. (Cl. 57-65) The cradle assembly of this invention forms part of a cable stranding machine.

These machines are well known in the art in various forms and are provided for the purpose of building up relatively large twisted cables composed of a plurality of smaller strands which are fed concurrently to the nose-piece of the machine. The twisting of the strands into the cable proper is effected by rotating'the main shaft of the machine on which are in turn rotatably mounted a plurality of cradles constructed to support supply spools for the strands. The cradles are rotatably mounted on axes which are parallel to and radially olfset from the axis of the main shaft of the machine, so that the cradles rotate bodily about that axis as they in turn rotate, each on its own axis which is parallel to the axis of the main shaft.

Each cradle is constructed so as to in turn rotatably support the strand spool thereon, the axis of which rotation for each cradle is at right angles to the axis of rotation of the spool. The cradle assemblies and loaded strand spools are relatively heavy, with the result that their planetary motion about the axis of the main shaft of the machine results in the development of very large operational stresses which in turn require not only a heavy construction for the main parts of the machine but also for the cradles.

As is well understood in the art the cradle frames, due to the reversal of forces encountered as they revolve bodily about the axis of the main shaft, alternately subject the side members of the cradles to rapidly and successively occurring maximum and minimum stresses. Thus, since each side member of the cradle is alternately subjected to a maximum stress, each cradle has to be of sufiiciently heavy construction to withstand such stresses.

The prime purpose of this invention is to provide a novel arrangement in which the side frame members of each cradle are cross-connected or tied together during operation of the machine so that the stresses applied to one side member will be transmitted to and divided with the other side member. This shifting of stresses occurs alternately as the cradle revolves not only about the axis of the main shaft of the machine, but on its own axis.

Further, in accordance with this invention the crossconnection of the side frame members of the cradle is effected by means of a tie bar which lies axially .of the strand spool, rotatably mounted on the cradle, and passes through the core of the spool so that it may not escape from the cradle during the operation of the machine.

A very important object of this invention is to provide a construction in which the tie bar cannot accidentally become disengaged from the assembly and thereby allow the strand spool to escape while the machine is in operation.

Further in accordance with this invention it is proposed to provide a construction in which the bearings for rotatably supporting the strand spool are capable of endwise movement withrespect to each other under the in- 11 and 12.

2,903,842 Patented Sept. 15, 1959 fluence of the tie bar, so that when the spool is mounted these hearings, which are the radial thrust type, are preloaded without stressing the side frame members on the cradle.

Further in accordance with this invention, provision is made, after the spool is mounted in the cradle, for locking the bearing assemblies therefor in the cradle so that in cooperation with the tie bar cross-connection of the side frame members is effected for transference of the stresses back and forth in the operation of the machine.

Other and more detailed objects of the invention will be apparent from the following description of the embodiment thereof illustrated in the accompanying drawings including the advantage that by this construction the cradles may be of lighter construction than otherwise possible.

In the accompanying drawings,

Figure 1 is an elevational view of suflicient of a planetary cable stranding machine to illustrate this invention showing one of the cradles in the plane with the strand spool mounted therein;

Figure 2 is a side elevational view of the cradle;

Figure 3 is a cross-sectional View taken on the line 3--3 of Fig. 1; and

:Figure 4 is a cross-sectional detail view taken on the line 4-4 of Fig. 3.

As diagrammatically illustrated, a planetary cable stranding machine includes a main rotor shaft 10, which is rotatablymounted in bearings, not shown, and which is provided at the cradle positions with radial arms or spiders Rotatably mounted in suitable bearings .14 and 15, at the outer ends of these arms, is the cradle which is generally indicated by the reference numeral 13. This cradle is thus rotatably mounted on its longitudinal axis at l the ends of the arms l1 and 12.

The cradle 13 is a generally rectangular open frame which includes the side frame members 19 and 20, formed to provide a pair of aligned bearing housings 17 and 18.

Mounted in the bearing housings 17 and 18 are a pair of rotatable strand spool support pintles, each of which includesv tapered roller bearings as a part thereof.

Thus the righthand pintle assembly of Fig. 3 includes a pair of fixed outer roller races 21 mounted in annular seats formed in the bearing housing 17. Associated with these races are a pair of inner races 22, which are mounted on a flanged sleeve 23 and locked thereon by means of a threaded locking ring 24 engaging threads on the unflanged end of that sleeve. Interposed between the race pairs 21 and 22 are a series of tapered bearing rollers 25 and 26 mounted in any suitable form of roller cages in accordance with well understood practice in the bearing art.

Secured by means of machine screws, as shown in Fig. 3, on the flanged end of the sleeve 23, is a truncated conical nosepiece 27. Also mounted on the sleeve attached to the nosepiece is a grooved pulley 28 which forms part of the usual friction brake commonly used in machines of this type but of no special importance herein. Projecting from the left hand face of the pulley is a pin 29 adapted to engage a suitably positioned aperture in the 'end member of the strand spool 16, so as to insure conjoint rotation of the strand spool 16 with the nosepiece 27 r nel with a radially positioned flange on the pulley 28,

31-,formingpart of the lefthand pintle assembly.-. Mounted inthissleeve, in suitably shapedandpositioned'. seats, are-a .pair of outer. bearing. races. 33, .which cooperate.

with a pair of'inner bearing races 34 to provide seats forthetapered bearing rollers 35.,and. 36. held in r'oll'er bearingcages. The inner races 34are' mounted on a rotatablesleeve 48 which is provided with a truncated.

conicalnosepiece 37, secured to its.end by means of machinescrews, as shown. These racesare confined to the sleeve at the other end by means .offa flange .38

An axial motion limiting.

48 .and. 23, to permit the passageof a. headed tie bar 40 therethrough. The unheaded endof the tie bar is threaded; as at 41, to engage the threads inthe central bore'of the disc 30. The enlarged end 42. of the tie bar is provided with a hexagonal shape, as illustrated. The passage in disc 39 is counterbored at 45 and theresulting wall is provided with two radially aligned notches 46, see.

Fig. 4. Aradial pin is fastened in the bar,,40 who in the counterbore 45. A loose ,washer 43,lies.under.the

wrench head 42. A disc 53.is held between theflange.

38-and the adjacent inner race 34. A sealing ring]54, contacting disc 53, is seated in, an annular groovein the. inner face of disc 39. A similarlymounted .sealiilgv ring- 55 contacts the outer face of the nosepiece 371 Thus the lefthand pintle assembly is also. sealed offagainst dirt and moisture, as in the case of therighthand pintle assembly.

As illustrated. in Fig.2, the sleeve- 31 can be locked in 'various axial positions in thebearing housing. 18 by means of a pair of threaded blocks 56 lying in a cavity formed in the .frame member 20; These blocks are provided with reversely threaded passages and a clamp.

bolt 57, having properly positioned reversely threaded sectionseng-aging the threads of the clamping blocks.

A spool is mounted in the cradle by releasing the clamp:

ingblocks 56 and unscrewing-the'tie .bar 40 so that the. lefthand pintle'assembly 31 can slide to the'left.v The reel which has a hollow barrel or core is thenpositioned so that at one end it engages the nosepiece 27, whereupon.

the-bar 40 is.replaced with the lefthand pintleassembly moving backnto the right so that its nosepiece 37 engages. The tie-bolt 401's. drawn up tight, causing the spool to be clamped between.

the, other end of the spool barrel.

the nosepieces. The ends of the spool barrel are preferably taperedto cooperate with the conical formation of the nosepieces, with the result that the spool will be centered concentrically with the axis of the pintles.

As the tie. bar is drawn up tight the bearings nearest the nosepieces 27 and 37 respectively, are preloaded and-this results in the fact that the tie bar pulls the lefthand pintle assembly towards the righthand pintle assembly fixed in the frame member 17. Upon-the'completion of these'procedural steps it will be seen that the side frame members 19 and 20 are not tied together or preloaded. The clamping blocks 43 are then drawnup.;tight to prevent any rotational or axial movement of the-ilefthandpintle assembly. The bearings remain preloaded and thespool, Qfcourse, is clamped between. the nosepieces, but the sideframe members stilLarenot stressed by, the tie bar understatic conditions.

Omthe otherhand, when themachineis inoperation. and: subjected .to theistressesidiscussed .at the beginning;

of this disclosure, the stresses, which are alternately applied to the side frame members, will be divided between them. To state this condition a little difierently, as the stresses build up to a maximum in one side frame member, it will be distributed or transferred to the relatively unstressed side member and this condition will alternate backsand forth as the machine operates. Thus, it ispossible to make the. cradle of a lighter construction than would be required were it not possible. to. divide'the operational loads between both:

side'frame members.

If centrifugal force acts toward the right, the bearing nearest disc.27 will be loaded by it in addition to its pre-load. The tie bar divides this additional load with the opposite frame member only.

Other types of bearings may be used instead of Timken, as shown.

The pin 44 on the tie bar 40, in cooperation with the notches 46, provides a very important safety factor. The total thread engagement. of the bar 40,with the cap 30 is longer than the normal lefthand pintle assembly movement, necessary to free the spools so that they can be-removed. In the clamping or ready to operate position,

the tie bar 40 cannot become loose and escape because,

if it accidentally starts to unscrew the pin 44 will press against the wall at the outer end of the counterbore 45. Should the pin 44 happen to align with and enter the notches46, the.bar 40 cannot turn, i.e. unscrew, further.

Should the clamping wedges 56 become loose accidentallyso that the lefthand pintle assembly can work to the.

left, successively freeingthe tie bar 40, the tie bar cannot get freebecause'itis-still threadedly engaged with the cap 30 when the lefthand pintle assembly has moved the maximum distance to the .left, as determined by the limit screw 50, and the righthand end wall of slot 49.- It follows, therefore, that under no condition can the tie bar 405get free and release. the spool 16. This is an important safety feature'for these machines,

From the above description it will be apparent to those skilled inthe art that thedetails of the structure selected herein to exemplify this invention may be varied by those skilled .inthe .art without departure from the novel combination and functional cooperations thereof. It is de-. sired, therefore, that. the scope of protection afforded hereby be determined by the appended claims.

What isclaimed is:

1. Inacable stranding machine, a rotatable spool sup,- porting .cradle havinga pair:of side frame members, a

pintlepassembly fixed in one of said members including a .rotatablespool supporting fixture journaled in a thrust bearing, a second pintleassembly slidably mounted in the other frame member and including a rotatable spool supporting: fixture journaled in a thrust bearing, tension. meansengaging said second pintle assembly and the opposite frame member for preloading said bearings while clampinga spool between said fixtures, means for lock-.

ing said second pintle assembly against movement in its frame'member, and cooperating means on said second pintle assembly-and 'said tension means for preventing their accidental disconnection.

2. In the combination of claim 1, said tension means axial movement with respect thereto.

3. In the combination of claim 1, said tension means including a tie bar, engaging the outer end of the second pintle assembly, and a threaded plate secured to the outer face of the frame member in which said first pintle as sembly ismounted, said tie bar threadedly engaging it, said cooperating meanson said second pintle assembly including-means onsaid ,tie bar for preventing relative-1 axialmovement ;While. allowing .relativejrotational movement therebetween, and means on said second pintle assembly for limiting sliding movement thereon so that threaded disengagement between said plate and tie bar is impossible as a result of sliding movement of sad second pintle assembly.

4. In the combination of claim 1, said tension means comprising a headed tie bar passing through said second pintle assembly and engageable on the outer face of the assembly at the head of said bar, the other end of said bar threadedly engaging the opposite frame member, and said cooperating means including a pin secured to said tie bar adjacent its head for normally preventing axial movement of the tie bar with respect to the second pintle assembly.

5. In the combination of claim 1, said tension means References Cited in the file of this patent UNITED STATES PATENTS 2,177,812 Robbins et a1. Oct. 31, 1939 2,787,884 Bruestle Apr. 9, 1957 2,860,479 Wheater Nov. 18, 1958 

